This is a resubmission of an application to purchase equipment to support a state-of-the-art shared Cardiovascular Physiology Resource (CPR) for small animals consisting of a high resolution, digital ultrasound machine (Vevo 2100) and an invasive hemodynamic system that would allow simultaneous imaging and hemodynamic interrogation. The proposed resource would address a critical need in this institution for a modern facility capable of sophisticated cardiovascular physiology assessment located at a single site and would convert the existing, limited, imaging resource to a comprehensive, single-site physiology resource. The proposed resource would upgrade an existing mechanical ultrasound machine that is suboptimal for cardiac physiology with a solid-state, electronic, high resolution ultrasound machine. In addition, the availability of a companion hemodynamics system would allow researchers to perform simultaneous invasive hemodynamic measurements in small animals, not currently feasible. The proposed resource will support 5 major and 4 minor users from the Departments of Medicine (Cardiology), Pediatrics, Anesthesiology, School of Public Health and Biomedical Engineering. All major users have qualifying NIH-funded projects that specifically include extensive cardiovascular physiology studies that are currently available piece-meal or through extramural collaborations. All major users will have access to the instrument and training through an established and proposed CPR infrastructure. Institutional monies and usage charges will be used to support service contract and other critical upgrades. This strategy has been successfully implemented for the imaging resource over the last four years and we foresee no difficulty in continuing that arrangement for the proposed CPR. Although we anticipate a high use percentage for the CPR, we will reserve 20% time for new users. The existing imaging resource has a track record of education, training, and productivity with several lab groups at Johns Hopkins University. The proposed CPR will be the only available cardiovascular physiology facility in an institution with a vibrant and highly productive group of basic cardiovascular researchers. Since the new Vevo 2100 contains significant and scientifically meaningful technical upgrades and there is an impending lack of parts and service support for the existing Vevo 770, the requested instrumentation is critical to continue and advance the scope of this research momentum. Public Health Relevance: Small animal models of cardiovascular disease are critical to understanding mechanisms and developing new therapies, however, an essential component of this effort is careful and detailed evaluation of cardiovascular physiology usually performed using a combination of invasive and non-invasive methods. The proposed Cardiovascular Physiology Resource will provide modern, sophisticated equipment for comprehensive small animal physiology studies in a convenient, single-site facility for a large group of highly productive cardiovascular researchers.